Detergents have hitherto been developed with a view to attaining improvement both in cleaning function and in imparting conditioning effects and mildness. With diversification of lifestyles, needs of consumers are becoming more diverse than in the past. Accordingly, consumers request detergents having various appearances or various functions.
With regards to the appearance, a pearlescent appearance is given to detergents in order to make them look luxurious and make consumers feel rich, while with regards to the function, detergents are requested to have not only detergency, but also, in the case of a shampoo, various functions capable of providing hair with a soft feel, manageability, easy combing property and the like.
Alkylene glycol mono- or di-alkyl esters are known as a pearling substance. Their alkyl chain length however differs widely, owing to the raw materials used so therefore the desired pearlescent appearance cannot be attained readily. For the purpose of imparting hair with a soft feel, manageability, or easy combing property, it is known to make the pH of a detergent acidic, which however leads to the decomposition of the ester of the pearling agent, whereby causing separation and impairment of the pearlescent appearance to seriously damage the stability of the composition.